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Traffic control signals are lights that use the colours green, yellow and red to control the flow of traffic at intersections or where roadways merge. The colour of the light determines which stream of traffic has the right of way. The traffic control signal may be vertical or horizontal.
The order of lights for a vertical traffic control signal is red at the top, yellow in the centre, and green at the bottom.
The order of lights for a horizontal traffic control signal is red on the left, yellow in the centre, and green on the right.
Solid red light
Drivers facing a traffic control signal displaying a solid red light must bring their vehicles to a complete stop before the stop line or crosswalk that is directly in front of the vehicle. If there is no stop line or crosswalk, drivers must stop before the intersection. Vehicles must remain stopped at the red light until it turns green, unless safely turning right after stopping.
A solid double red light has the same meaning as a single red light.
Right turn at red light – Unless a sign prohibits the turn, a driver may turn right at a red light after stopping completely before the stop line or crosswalk, if the turn can be made safely after yielding to other traffic.
Left turn at red light – Unless a sign prohibits the turn, the only left turn permitted at a red light is onto a one-way street from a one-way street. This turn is only permitted after the vehicle is brought to a complete stop before the stop line or crosswalk, and if the turn can be made safely after yielding to other traffic.
Solid yellow light
When a green light changes to yellow, it warns that the light will change to red immediately and drivers must prepare to stop or clear the intersection. Drivers approaching an intersection with a solid (not flashing) yellow traffic control light must bring their vehicles to a complete stop before the stop line or crosswalk, unless a point has been reached at the intersection where stopping cannot be done safely. If there is no stop line or crosswalk, vehicles must stop before the intersection.
Drivers already in the intersection and facing a yellow light must safely clear the intersection.
Solid green light
Drivers facing a solid green traffic control light are permitted to travel through the intersection without stopping, unless required to yield to oncoming traffic when turning left or to pedestrians in the crosswalk when turning right or left.
When approaching a green light, anticipate that it will turn yellow. A "stale" green light means the light has been green for a while and will turn yellow soon. A good tip is to check the pedestrian walk light at the intersection. If it shows the WALK symbol, the light will stay green. If it shows the DON'T WALK symbol, be ready to stop. If the traffic light does change, the driver must stop before the intersection if it can be done safely.
Green arrow with green light
Drivers facing a traffic control light with a green arrow and solid green traffic control light may enter the intersection and proceed without yielding in the direction indicated by the arrow. Drivers facing the green light may also proceed in the other directions when it is safe and legal.
Green arrow with red light
Drivers facing a traffic control light with a green arrow and a red control light may enter the intersection and proceed without stopping only in the direction indicated by the arrow.
Flashing red light
Drivers facing a flashing red traffic control light must stop before the stop line or crosswalk. If there is no stop line or crosswalk, drivers must stop before the intersection. Drivers should proceed only when it is safe and after yielding the right-of way. The flashing red light is treated like a stop sign.
When the lights in all directions are flashing red the intersection becomes a 4-way stop.
Flashing yellow light
Drivers facing a flashing yellow traffic control light may proceed with caution after yielding to pedestrians and other vehicles within the intersection.
Flashing green light
Drivers facing a flashing green traffic control light are permitted to go through, turn left or turn right without stopping. Opposing traffic will be facing a red light; however a driver must still yield to pedestrians or other vehicles lawfully in the intersection.